Fluid filter

ABSTRACT

An improved fluid filter is provided that has a rigid apertured center tube which is attached to a fluid outlet. Once the center tube assembly is secured to the fluid outlet, a tubular filter element is replaceably secured around the center tube. By incorporating a rigid center tube, the tubular filter element can be constructed so that it does not require a self contained supporting structure. Thus, by eliminating an integral supporting structure, the filter element can be made solely of combustable materials, aiding in the disposal of used filter elements.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a filter system designed to accommodatea filter element having no center supporting tube. This allows a filterelement to be constructed solely of combustible material, thus allowingthe filter element to be completely incinerable.

2. Description of the Related Art

In industrial filtering applications, often the material which is to befiltered contains contaminants which must be removed and disposed of ashazardous waste. One of the acceptable ways of disposing of many typesof hazardous waste is incineration performed by a licensed hazardouswaste disposal facility.

One problem which previous filter systems present is that the filterelement onto which the contaminates adhere have generally contained ametal or other rigid, non-combustible center support member. In order toincinerate these filter elements, the support member must either bemanually removed from the filter element prior to the incineration andthen separately disposed of as hazardous waste or, alternately, theentire filter element must be shredded prior to incineration.

Removal of the center support member prior to incineration presentssafety problems to the workers performing the removal, adds to the costof disposal, and increases the risk of liability to the companygenerating the waste. This increase in risk of liability is due to thefact that the removed support members are considered hazardous wastewhich must be disposed of in a licensed hazardous waste landfill. As acontributor to a hazardous waste landfill which may sometime be declareda Superfund site, the generating company, the disposal company and anytransporting company which was employed to deliver the support membersto the landfill, may all face future liability for the disposal. Thus,both the generating company and the disposal company would prefer toavoid this option since under current hazardous disposable waste laws,they remain liable for their hazardous waste from "cradle-to-grave".

On the other hand, in order for the entire filter element to beincinerated, a disposal facility must first be located which has thecapability of shredding materials prior to incineration. Second, sincethe non-combustible elements of the filter element will pass through thehazardous waste incinerator and will exit as solid waste which isnormally disposed of as hazardous waste in a hazardous waste landfill,the generating company retains the potential Superfund liability withthis option also. This is true despite the fact that the material is nothazardous waste, since all contributors to a landfill which laterbecomes a Superfund site are liable for ensuing cleanup costs regardlessof the types of materials they contributed. For these reasons, shreddingand incinerating the entire filter elements is also an unattractiveoption.

The only other viable option available for disposal of most filterelements is to bury the entire filter element in a hazardous wastelandfill. This option is costly and increases the risk of Superfundliability since the containers in which the filter elements are sealedfor burial will eventually be breached by the soil's natural chemicalprocesses, thus, releasing the contaminants into the soil.

Thus, to avoid potential liability, it is desirable to have completelyincinerable filters. The present invention addresses this problem byproviding a filter system having a permanent center tube assembly ontowhich fully incinerable filter elements may be replaceably attached.

SUMMARY OF THE INVENTION

The present invention briefly is a filter system having an elongatedhollow apertured center tube assembly around which fully incinerablefilter elements may be replaceably secured. The center tube assembly maybe composed of one or more interlocking tube sections which are attachedto each other end-to-end by means of an intermediate connecting member.Each of the interlocking tube sections is composed of an interlockingupper female tube and a corresponding lower male tube. A bottom end ofthe tube assembly abuts a filter attachment means and is held invertical alignment therewith by means of a central rod which secures tothe filter attachment means and extends upwardly therefrom, passingsequentially through openings provided in a bottom flange member locatedat the bottom end of the center tube assembly, a hub portion provided oneach intermediate connecting member for center tube assemblies comprisedof more than one interlocking tube section, and a top flange memberlocated at a top end of the center tube assembly. A jam nut tightensonto a threaded portion provided on a top end of the rod, abutting thetop flange member in order to secure the center tube assembly to thefilter attachment means. The filter element is then slid down around thecenter tube assembly. A yoke provided with a central opening throughwhich the threaded portion of the rod passes, is secured to the filtersystem by tightening a nut onto the threaded portion of the rod so thatthe nut tightens against washers which abut the yoke. As the nut istightened, a compressible bottom sealing gasket provided on a bottom endof the filter element seals the filter element to the filter attachmentmeans and a compressible top sealing gasket provided on a top end of thefilter element seals the filter element to the yoke.

In use, a medium to be filtered passes inwardly through a pleated filtermedium provided on the filter element, through the apertured centeredtube assembly, then downwardly through the opening in the bottom flangemember which communicates with a fluid passageway provided in the filterattachment means as a means for the filtered medium to exit the filtersystem.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation of a filter system constructed according toa preferred embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line 2--2 of FIG. 1.

FIG. 3 is a cross-sectional view taken along line 3--3 of FIG. 1.

FIG. 4 is a top plan view of the filter system taken along line 4--4 ofFIG. 1.

FIG. 5 is a front elevation of a bottom flange removed from the filtersystem of FIG. 1.

FIG. 6 is a top plan view of the bottom flange taken along line 6--6 ofFIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings and initially to FIG. 1, there isillustrated a filter system 10 constructed according to a preferredembodiment of the present invention.

The filter system 10 is provided with a vertically oriented central rod12, having a bottom end 14, which is attached by means of a nut 15 orotherwise to a filter attachment means 16, and a top end 18 providedwith a threaded portion 20. The filter attachment means 16 is providedwith a fluid passageway 22 therethrough. An upwardly oriented innerretaining lip 24 is provided concentrically around the fluid passageway22. The filter attachment means 16 is provided with a horizontallyoriented ledge 25 attached circumferentially and extending outwardlyfrom the inner retaining lip 24. An upwardly oriented outer retaininglip 26 is provided on the ledge 25 of the filter attachment means 16 sothat the outer retaining lip is spaced away from the inner retaining lip24 and is spaced away from an outer edge 28 of the ledge 25.

An elongated apertured center tube assembly 30, having a top end portion32 and a bottom end portion 34, attaches by means of a bottom flangemember 36 provided on the bottom end portion 34 of the center tubeassembly 30 to the filter attachment means 16 so that the center tubelower end rests between the inner and outer retaining lips 24 and 26.Bottom flange member 36 is provided with a central opening which allowscommunication between the center tube assembly 30 and the fluidpassageway 22 of the filter attachment means 16.

The center tube assembly 30 is composed of at least one interlockingtube section 38. The filter system 10, as illustrated in FIG. 1, employstwo interlocking tube sections 38. Although not illustrated, the presentinvention also includes filter systems 10 employing one or more than twointerlocking tube sections 38. Each interlocking tube section 38 iscomposed of a lower male tube 40 and an upper female tube 42. The tubes40 and 42 are held together by means of ears 41 provided on an upper end43 of each of the lower male tubes 40 that engage corresponding openings44 provided in a lower end 45 of each of the female tubes 42.

Each of the male tubes 40 is provided with a lower end 46. When thecenter tube assembly 30 is composed of only one tube section 38, thelower end 46 of the solitary male tube 40 serves as the bottom end 34 ofthe center tube assembly 30 and, as such, secures to an upper end 48 ofthe bottom flange member 36. As best seen in FIGS. 1, 5 and 6, the upperend 48 of bottom flange member 36 is provided with an upwardly orientedsection 50 of decreased external diameter, and the lower end 46 of thelower male tube 40 is provided with a downwardly oriented section 52 ofincreased internal diameter so that the upwardly oriented section 50telescopically receives the downwardly oriented section 52. The upwardlyoriented section 50 is provided with ears 54 that engage correspondingopenings 55 (visible in the upper most tube section 38 in FIG. 1)provided in the downwardly oriented section 52 in order to secure thebottom end 34 of the central tube assembly 30 to the bottom flangemember 36.

As illustrated in FIG. 1, two or more tube sections 38 can be attachedconcentrically end-to-end by employing intermediate connecting members56. Each of the intermediate connecting members 56 has an upwardlyoriented upper end 58, a downwardly oriented lower end 60, and a middleportion 62 located between the two ends 56 and 60. Collectively, theends 56 and 60 and the middle portion 62 comprise a circumferentialflange portion of each of the intermediate connecting members 56.Referring also to FIG. 3, the middle portion 62 is provided with spokes64 oriented inwardly and attached centrally to a central hub 66. Thecentral hub is provided with an opening 68 therethrough for receivingthe rod 12.

Each of the lower ends 60 is decreased in external diameter, and anupper end 70 provided on each of the female tubes 42 is decreased ininternal diameter so that the lower ends 60 are telescopically receivedby the upper ends 70 of the interlocking tube section 38 locatedimmediately below. Each of the upper ends 70 is provided with openings72 for receiving corresponding ears 73 provided on each of the lowerends 60 to secure the intermediate connecting member 56 to the tubesection 38 located immediately below the intermediate connecting member56.

Likewise, each of the upper ends 56 is decreased in external diameter sothat the upper ends 56 telescopically receive the downwardly orientedsections 52 provided on the lower ends 46 of the male tube 40 in thetube section 38 located immediately above. Similarly, each of the upperends 58 is provided with ears 74 that engage the openings 55 provided inthe downwardly oriented section 52 of the male tube 40 of the tubesection 38 located immediately above in order to secure together theintermediate connecting member 56 and the tube section 38 immediatelyabove.

The upper end 70 of the female tube 42 located in the upper most tubesection 38 of the filter system 10 is telescopically received by a lowerend 76 having a reduced external diameter which is provided on a topflange member 78. The top flange member 78 is removably secured to thecenter tube assembly 30 and, therefore, the top flange member 78 doesnot have any ears for engaging the openings 72 provided on the upper end70 of the female tube 42 in the uppermost tube section 38.

The top flange member 78, shown in FIGS. 1 and 2, is provided with acontinuous upper end 80 that extends inwardly and is provided with acentral opening 82 therethrough for receiving the rod 12. Adjacent thecentral opening 82, the upper end 80 of flange member 78 forms anupwardly facing depression 84 into which a jam nut 86 is positioned whenthe jam nut 86 is tightened onto the threaded portion 20 of the rod 12in order to secure the center tube assembly 30 to the filter attachmentmeans 16.

The upwardly facing depression 84 is provided with a plurality ofpressure relief openings 88 that communicate through the top flangemember 78 and that permit liquids and gases from becoming trapped in thedepression 84.

Once the center tube assembly 30 has been secured to the filterattachment means 16, a hollow pleated filter element 90, having a topend 91 and a bottom end 92, is lowered around the center tube assembly30. The pleated filter element 90 comprises a top ring 93 to which a topsealing gasket 94 is attached, an opposite bottom ring 96 to which abottom sealing gasket 98 is attached, and a pleated filter medium 100extending between and sealing to the top and bottom rings 93 and 96.When used with the filter system 10 which has the center tube assembly30 attached thereto, the filter element 90 does not require a centersupport tube to be incorporated in the filter element 90. Therefore, thefilter element 90 can be made solely of combustible materials that canbe disposed of by incinerating.

Referring now to FIGS. 1 and 4, the filter element 90 is lowered intoplace so that the bottom sealing gasket 98 engages the ledge 25 of thefilter attachment means 16. Once the filter element 90 is in place, ayoke 102 provided with a central opening 104 therethrough is placed overthe top end 18 of the rod 12 so that the rod 12 extends through theopening 104. The yoke 102 is then lowered on the rod 12 until its outerperipheral area 103 is adjacent the top flange member 78 and engages thetop sealing gasket 94. A compressible washer 106 is next placed onto thethreaded portion 20 adjacent the yoke 102. A second washer 108 is thenplaced between the compressible washer 106 and a nut 110. The nut 110 istightened against the washers 106 and 108, thus compressing the top andbottom sealing gaskets 94 and 98 and, thereby, sealing the filterelement 90 to the filter attachment means 16 on the bottom end 92 and tothe yoke 102 on the top end 91.

In use, a medium to be filtered (not illustrated) passes through thepleated filter element 90, then through the apertured center tubeassembly 30 before exiting the filter assembly 10 via the fluidpassageway 22 of the filter attachment means 16. The center tubeassembly 30 supports the filter element 90, enabling it to withstanddifferential pressure exerted on it by the medium to be filtered (notillustrated).

When the filter element 90 becomes clogged, flow of the medium to befiltered (not shown) is discontinued in order to take the filter system10 out of service. After the filter system 10 is out of service, the nut110 is removed from the rod 12 and the washers 106 and 108 and the yoke102 are removed. The filter element 90 is then slipped upward andremoved from the center tube assembly 30. A fresh filter element 90 isthen inserted around the center tube assembly 30 and the yoke 102, thewashers 106 and 108 are replaced, and the nut 110 is re-tightened toseal the filter element 90 to the filter attachment means 16 and theyoke 102. The filter system 10 is then ready to be placed back inservice.

The claims and the specification describe the invention presented andthe terms that are employed in the claims draw their meaning from theuse of such terms in the specification. The same terms employed in theprior art may be broader in meaning than specifically employed herein.Whenever there is a question between the broader definition of suchterms used in the prior art and the more specific use of the termsherein, the more specific meaning is meant.

While the invention has been described with a certain degree ofparticularity, it is manifest that many changes may be made in thedetails of construction and the arrangement of components withoutdeparting from the spirit and scope of this disclosure. It is understoodthat the invention is not limited to the embodiments set forth hereinfor purposes of exemplification, but is to be limited only by the scopeof the attached claim or claims, including the full range of equivalencyto which each element thereof is entitled.

What is claimed:
 1. An Improved fluid filter comprising:an elongatedrigid apertured center tube having a top and a bottom end; an elongatedrod extending coaxially through said center tube and having a top and abottom end, the bottom end of the rod being secured to a filterattachment means having a fluid passageway therethrough, a portion ofsaid rod at said top end being threaded; a top flange member having acentral opening therethrough and a periphery in engagement with andclosing said center tube top end the top flange member central openingreceiving said rod therethrough; a means received on said rod adjacentto said top end thereof to thereby secure said top flange member againstsaid center tube and to thereby hold said center tube in communicationwith said filter attachment means; a tubular combustible filter elementreplaceably receivable on said center tube, the filter element having abottom end and a top end; top and bottom toroidal end caps sealablyclosing said filter element top and bottom ends, said bottom end capsealably engaging said filter attachment means providing closedcommunication between said tubular filter element and said filterattachment means fluid passageway; a yoke member having a centralopening therethrough receiving said rod and having an outer peripheralarea sealably engaging said top end cap; and nut means threadablyreceived on said rod adjacent to said top end thereof to retain saidyoke whereby by removing said nut means and thereby said yoke membersaid filter element is replaceable without disturbing said center tube,2. An improved filter according to claim 1 wherein said filter elementis comprised of a tubular filter media formed of a pleated member.
 3. Animproved filter according to claim 1 wherein said elongated aperturedcenter tube is comprised of a plurality of tubular sections joinedconcentrically end-to-end.
 4. An improved filter according to claim 1wherein said elongated apertured center tube comprises an upper centertubular section having upper and lower ends, a lower center tubularsection having upper and lower ends, an intermediate connecting memberhaving upper and lower ends and having a central hub portion with anopening therethrough receiving said rod and having a circumferentialflange portion telescopically receiving the upper and lower tubularsections and having integral spoke portions interconnecting said hub andcircumferential flange portions.
 5. An improved filter according toclaim 4 wherein each end of both said upper and lower center tubularsections is of increased internal diameter and wherein said top flangemember has a lower end of decreased external diameter, said bottomflange member has an upper end of decreased external diameter and saidintermediate connecting member has upper and lower end portions each ofdecreased external diameter whereby the upper end of said upper centertubular section telescopically receives the lower end of said top flangemember and the lower end of said upper center tubular sectiontelescopically receives the upper end of said intermediate connectingmember and whereby the upper end of said lower center tubular sectiontelescopically receives the lower end of said intermediate connectingmember, the lower end of said lower center tubular sectiontelescopically receives the upper end of said bottom flange member. 6.An improved filter according to claim 1 wherein the top flange member isprovided with pressure relief openings therethrough.